Operations ManagementCase study National Cranberry Cooperative - Operations Management-SCH-MGMT-670

Group :1. Deepika Gupta2. Saloni Shukla3. Sanya Talwar4. Raghav Goyal5. Zorawar Singh

1. What are the major reasons for trucks waiting and excessive worker overtime? Solution:Process flow in this case can be summarised as follows: The truck unloads its contents onto 5 conveyor belts. The conveyor belts shift the stock of cranberries onto temporary holding bins from where they are moved for emptying. The emptying process usually takes 7-8 minutes, unless there are any bottlenecks, in which case it may go upto 3 hours. The major root cause for truck waiting times and worker overtime is the bottleneck at Receiving Plant 1. If holding bins are unavailable on the second floor, the delivery trucks have to wait with the cranberries being full on the first floor receiving plant. Thus, trucks have to match upto the amount of cranberries already in the temporary holding bins. This is the bottleneck with the strategy of National Cranberries Cooperative and calls for a change in the overall strategy of the firm to augment capacity and address the issue of waiting times.

2. Draw the cranberry processing flow chart, showing the processing capacity at each stage and determine the maximum throughput rate of the plant Solution:

3. Plot the cranberry inventory (in bbls) build-up by hour on a busy day, with current resources and the processing start at 11:00 am. Determine the average waiting time of trucks, worker overtime, and their financial implications.Solution:The bottleneck for the process is the dryers. The capacity of the drying unit is 600 bbl /hour which is lower than the required 1050 wet bbl/day. The trucks start arriving at 7:00 AM and store the wet berries in storage bins (17 24, 25, 26, and 27). The total capacity of the bins is 3x400 + 8 * 250 = 3200 bbls. The trucks start waiting at 10.03 AM (3200 / 1050) Inventory buildup rate = arrival rate processing rate = 1050 bbl -600 bbl = 450 bbl / hourInventory buildup rate = arrival rate processing rate = 1050 bbl -600 bbl = 450 bbl / hourTotal inventory buildup = 4200 + 8 * 450 = 7800Total wait of the truck is calculated as follows:At the end of the day (12 hours), there will be 7800 left in the inventory. Out of this 3200 will be in the bins and 4600 will be waiting in the truck. It will take 4600/600 = 7.67 hours to clear them.Truck Waiting = 16.67 hoursWaiting time for all the trucks = 16.67 * (4600/2) = 511 hours

4. What is the effect of starting processing at 7:00 am during a busy season?Solution:The following assumptions are made for calculation purpose: On an average busy day, berries arrive continuously at rate of 15,00 bbls/ hour There are 20 busy days in an average growing season.Inventory buildup rate = arrival rate processing rate1050bbl - 600bbl =450 bblAt this buildup rate, wet bins will fill up in 3200/450 =7.11 hours. So the truck will start waiting ar 2:06pm. Total wait of the truck:Inventory at the end of the day (12 hours) = 450*12=5400bbl, of which 3200bbl will be in bins and rest 2200bbl will be in trucks. It will take 2200/600=3.67hours to empty the waiting It will take 2200/600=3.67 hours to empty the waiting trucks. So, inventory will start building from 7.11 hours to 15.67 hours. And at 10:40 PM there will be no truck waiting.Truck waiting = 15.67- 7= 8.67 hours.Waiting time for all tracks adds to=8.67 hrs x (2200/2)/75 = 127 hours

Although the plant operations are moved to 7 AM, the over time remains at 13 hours. On a busy day , 12600 out of 18000 bbl is wet. At an average processing rate of 600 bbl/ hour , it takes to 21 hours to process. Thus there is an overtime of 13 hours.

5. Make specific recommendations to improve the process performanceSolution :National Cranberry Cooperative is plagued with issues of truck waiting time and excessive overtime. It needs to review its strategy to being in efficiency in operations. Few recommendations that can help NCC augment efficiency are:

Commence process at 7 AM

Install 2 dryers

Add another grading line

Implementing these changes can help NCC achieve savings and contain excessive wait-times. These recommendations can reduce the work hours by 8 hours and help NCC save $194,040

Team TitleCompany NameCompany NameDepartment Name5* DumpersAt RP1

Holding bin

3* Main conveyers 3*Dechaffing 17-24

3*Separators 6*Conveyers 3*Dryers Destoning 1-16

4* Bagging 4* Bulk Bin 2* Bulk station 5-10 Mins

3*1500 bbls=4500 bbls

3*1500 bbls=4500 bbls

3*200 bbls=600 bbls

3*400 bbls=1200 bbls

800 bbls/hr

667 bbls/hr

2000 bbls/hr

3*Dechaffing25-27 3*1200 bbls=3600 bbls